Wednesday, March 30, 2011
Europe's workhorse in launching commercial satellites suffered an on-the-pad launch abort today seconds before it's boosters were to ignite.
The Vulcain 2 single main engine ignites in the final seven seconds before launch. During this time, computers in milliseconds checkout every aspect of the rocket to ensure it it safe to launch.
The engine ignited on time and was throttled up to nominal chamber speed. Spoke billowed up to the height of the rocket as the engine was commanded to shut down.
An issue with the engine was likely detected according to arianespace, however it is too soon to know the cause for another day.
"The cryogenic main engine’s checkout process was not completed successfully, preventing the boosters’ ignition and thereby aborting the launch," Arianespace Chairman & CEO Jean-Yves Le Gall stated minutes after the shutdown.
"The Ariane 5 and its two payloads remain in a safe mode on the launch pad, and the vehicle will be returned to the Final Assembly Building for diagnostics," Le Gall added.
During the next week, Ariane 5 will be positioned in it's vertical hanger and studied.
The core engine under goes a chill down process just over three hours before ignition, and after the super cold liquid oxygen and liquid hydrogen fuels are loaded into the main stage ninety minutes earlier.
As the main engine ignites seven seconds before the twin boosters ignite, computers on board the Ariane take over three seconds after engine ignition to verify the rocket is ready.
Twin fuel lines are retracted near the top of the rocket as the engine nears 100%.